1. Field of the Invention
The present invention relates to a wake-up apparatus and wake-up method for a low power sensor node, and more particularly, to a wake-up apparatus and wake-up method, which can extend the battery life of the sensor node and minimize the amount of power consumed by an entire sensor network by minimizing unnecessary power consumption of the sensor node.
The present invention is derived from a research project supported by the Information Technology (IT) Research & Development (R&D) program of the Ministry of Information and Communication (MIC) and the Institute for Information Technology Advancement (IITA) [2005-S-106-03, Technology Development of Sensor Tag and Sensor Node for RFID/USN].
2. Description of the Related Art
One of the main features of a ZigBee or ubiquitous sensor network is that it provides and controls a low power system. The ZigBee or ubiquitous sensor network uses frequency bands of 868.3 MHz, 915 MHz, and 2.45 GHz based on IEEE 802.15.4-2006 standard. Available channels, a transmission speed of data, and a transmission method can be classified according to the frequency bands used.
The ZigBee or ubiquitous sensor network is used in various fields of application including a home network system.
For example, the ZigBee or ubiquitous sensor network can be widely classified according to types of commercial sensors and fields of fire sensing in terms of forest fires, control and management of factory facilities, home network automation systems and observation of facilities, and management of patients in hospitals.
Conventionally, in order to reduce power consumption of a sensor node used in various ubiquitous sensor networks, research and development in terms of the implementation of a low power system that controls management of schedules, communication, data transmission, and the like by using software, have been carried out.
Such a low power system mainly has a function for reducing power consumption of the entire sensor network rather than a function for reducing or controlling power consumption of each sensor node, and thus difficulties arise when controlling and managing an individual sensor node and the low power system.
Herein, a method of controlling an individual sensor node is used to minimize power consumption in the ubiquitous sensor network. For example, research has been carried out into the development of a power source unit which can reduce power consumption of a power source unit used in the sensor node, and the provision of a new structure of wireless communication having a wireless communication function.
In order to develop the power source unit, research involving a solar battery for collecting energy has been carried out. Also, methods have been proposed to reduce power consumption by simplifying a structure of a sensor node and enabling wake-up only when necessary while in a sleep state.